|
Propanal
Propionaldehyde or propanal is the organic compound with the formula CH3CH2CHO. It is the 3-carbon aldehyde. It is a colourless, flammable liquid with a slightly fruity odour. It is produced on a large scale industrially. Production Propionaldehyde is mainly produced industrially by hydroformylation of ethylene: :CO + H2 + C2H4 → CH3CH2CHO In this way, several hundred thousand tons are produced annually. Laboratory preparation Propionaldehyde may also be prepared by oxidizing 1-propanol with a mixture of sulfuric acid and potassium dichromate. The reflux condenser contains water heated at 60 °C, which condenses unreacted propanol, but allows propionaldehyde to pass. The propionaldehyde vapor is immediately condensed into a suitable receiver. In this arrangement, any propionaldehyde formed is immediately removed from the reactor, thus it does not get over-oxidized to propionic acid. Reactions Propionaldehyde exhibits the reactions characteristic of alkyl aldehydes, e.g. ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Acrolein
Acrolein (systematic name: propenal) is the simplest unsaturated aldehyde. It is a colorless liquid with a piercing, acrid smell. The smell of burnt fat (as when cooking oil is heated to its smoke point) is caused by glycerol in the burning fat breaking down into acrolein. It is produced industrially from propylene and mainly used as a biocide and a building block to other chemical compounds, such as the amino acid methionine. History Acrolein was first named and characterized as an aldehyde by the Swedish chemist Jöns Jacob Berzelius in 1839. He had been working with it as a thermal degradation product of glycerol, a material used in the manufacture of soap. The name is a contraction of ‘acrid’ (referring to its pungent smell) and ‘oleum’ (referring to its oil-like consistency). In the 20th century, acrolein became an important intermediate for the industrial production of acrylic acid and acrylic plastics. Production Acrolein is prepared industrially by oxidation ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Propanol
There are two isomers of propanol. * 1-Propanol, ''n''-propanol, or propan-1-ol : CH3CH2CH2OH, the most common meaning *2-Propanol, Isopropyl alcohol, isopropanol, or propan-2-ol : (CH3)2CHOH See also * Propanal (propionaldehyde) differs in spelling from propanol by a single letter and is a different compound. * Propranolol Propranolol, sold under the brand name Inderal among others, is a medication of the beta blocker class. It is used to treat high blood pressure, a number of types of irregular heart rate, thyrotoxicosis, capillary hemangiomas, performance an ... is a drug used for reducing blood pressure and hand tremors. {{Authority control Alkanols ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Alkyd
An alkyd is a polyester resin modified by the addition of fatty acids and other components. Alkyds are derived from polyols and organic acids including dicarboxylic acids or carboxylic acid anhydride and triglyceride oils. The term ''alkyd'' is a modification of the original name "alcid", reflecting the fact that they are derived from ''alc''ohol and organic ac''id''s. The inclusion of a fatty acid confers a tendency to form flexible coatings. Alkyds are used in paints, varnishes and in moulds for casting. They are the dominant resin or binder in most commercial oil-based coatings. Approximately 200,000 tons of alkyd resins are produced each year.. Published online: 15 January 2003. The original alkyds were compounds of glycerol and phthalic acid sold under the name Glyptal. These were sold as substitutes for the darker-colored copal resins, thus creating alkyd varnishes that were much paler in colour. From these, the alkyds that are known today were developed. Manufacture Alky ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Comet
A comet is an icy, small Solar System body that, when passing close to the Sun, warms and begins to release gases, a process that is called outgassing. This produces a visible atmosphere or coma, and sometimes also a tail. These phenomena are due to the effects of solar radiation and the solar wind acting upon the nucleus of the comet. Comet nuclei range from a few hundred meters to tens of kilometers across and are composed of loose collections of ice, dust, and small rocky particles. The coma may be up to 15 times Earth's diameter, while the tail may stretch beyond one astronomical unit. If sufficiently bright, a comet may be seen from Earth without the aid of a telescope and may subtend an arc of 30° (60 Moons) across the sky. Comets have been observed and recorded since ancient times by many cultures and religions. Comets usually have highly eccentric elliptical orbits, and they have a wide range of orbital periods, ranging from several years to potentially several mill ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Milky Way Galaxy
The Milky Way is the galaxy that includes our Solar System, with the name describing the galaxy's appearance from Earth: a hazy band of light seen in the night sky formed from stars that cannot be individually distinguished by the naked eye. The term ''Milky Way'' is a translation of the Latin ', from the Greek ('), meaning "milky circle". From Earth, the Milky Way appears as a band because its disk-shaped structure is viewed from within. Galileo Galilei first resolved the band of light into individual stars with his telescope in 1610. Until the early 1920s, most astronomers thought that the Milky Way contained all the stars in the Universe. Following the 1920 Great Debate between the astronomers Harlow Shapley and Heber Curtis, observations by Edwin Hubble showed that the Milky Way is just one of many galaxies. The Milky Way is a barred spiral galaxy with an estimated D25 isophotal diameter of , but only about 1,000 light years thick at the spiral arms (more at the bulge) ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Sagittarius B2
Sagittarius B2 (Sgr B2) is a giant molecular cloud of gas and dust that is located about from the center of the Milky Way. This complex is the largest molecular cloud in the vicinity of the core and one of the largest in the galaxy, spanning a region about across. The total mass of Sgr B2 is about 3 million times the mass of the Sun. The mean hydrogen density within the cloud is 3000 atoms per cm3, which is about 20–40 times denser than a typical molecular cloud. The internal structure of this cloud is complex, with varying densities and temperatures. The cloud is divided into three main cores, designated north (N), middle or main (M) and south (S) respectively. Thus Sgr B2(N) represents the north core. The sites Sgr B2(M) and Sgr B2(N) are sites of prolific star formation. The first 10 H II regions discovered were designated A through J. H II regions A–G, I and J lie within Sgr B2(M), while region K is in Sgr B2(N) and region H is in Sgr B2(S). The 5-parsec-wi ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Molecular Cloud
A molecular cloud, sometimes called a stellar nursery (if star formation is occurring within), is a type of interstellar cloud, the density and size of which permit absorption nebulae, the formation of molecules (most commonly molecular hydrogen, H2), and the formation of H II regions. This is in contrast to other areas of the interstellar medium that contain predominantly ionized gas. Molecular hydrogen is difficult to detect by infrared and radio observations, so the molecule most often used to determine the presence of H2 is carbon monoxide (CO). The ratio between CO luminosity and H2 mass is thought to be constant, although there are reasons to doubt this assumption in observations of some other galaxies. Within molecular clouds are regions with higher density, where much dust and many gas cores reside, called clumps. These clumps are the beginning of star formation if gravitational forces are sufficient to cause the dust and gas to collapse. History The form of molecular ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Organic Synthesis
Organic synthesis is a special branch of chemical synthesis and is concerned with the intentional construction of organic compounds. Organic molecules are often more complex than inorganic compounds, and their synthesis has developed into one of the most important branches of organic chemistry. There are several main areas of research within the general area of organic synthesis: ''total synthesis'', ''semisynthesis'', and ''methodology''. Total synthesis A total synthesis is the complete chemical synthesis of complex organic molecules from simple, commercially available petrochemical or natural precursors. Total synthesis may be accomplished either via a linear or convergent approach. In a ''linear'' synthesis—often adequate for simple structures—several steps are performed one after another until the molecule is complete; the chemical compounds made in each step are called synthetic intermediates. Most often, each step in a synthesis refers to a separate rea ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Tert-Butylamine
''tert''-Butylamine is an organic chemical compound with the formula (CH3)3CNH2. It is a colorless liquid with a typical amine-like odor. ''tert''-Butylamine is one of the four isomeric amines of butane, the others being ''n''-butylamine, ''sec''-butylamine and isobutylamine. Preparation ''tert''-Butylamine is produced commercially by direct amination of isobutylene using zeolite catalysts: :NH3 + CH2=C(CH3)2 → H2NC(CH3)3 The Ritter reaction of isobutene with hydrogen cyanide is not useful because it produces too much waste. :(CH3)2C=CH2 + HCN + H2O → (CH3)3CNHCHO :(CH3)3CNHCHO + H2O → (CH3)3CNH2 + HCO2H In the laboratory, it can be prepared by the hydrogenolysis of 2,2-dimethylethylenimine, or via ''tert''-butylphthalimide. Uses ''tert''-Butylamine is used as an intermediate in the preparation of the sulfenamides such as ''N''-''tert''-butyl-2-benzothiazylsulfenamide and ''N''-''tert''-butyl-2-benzothiazylsulfenimide. As rubber accelerators, thes ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Lilial
Lilial (a trade name for lily aldehyde, also known as lysmeral) is a chemical compound commonly used as a perfume in cosmetic preparations and laundry powders, often under the name ''butylphenyl methylpropional''. It is a synthetic aromatic aldehyde. It was banned for use in cosmetics by the EU in March 2022 after being found to be harmful to fertility. Synthesis Lilial is produced at BASF through a double anodic oxidation of 4-''tert''butyl-toluene on >10,000 ton per year scale. Properties Lilial is commonly produced and sold as a racemic mixture; however, testing has indicated that the different enantiomers of the compound do not contribute equally to its odor. The (''R'')-enantiomer has a strong floral odor, reminiscent of cyclamen or lily of the valley; whereas the (''S'')-enantiomer possesses no strong odor. : Like most aldehydes, lilial is not long term stable and tends to slowly oxidize on storage. Safety The Scientific Committee on Consumer Safety (SCCS, scientific com ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Helional
Helional (from heliotropin, from which is it commonly derived) is a chemical compound used as a perfume in soap and laundry detergent. Chemically it is an aldehyde with a hydrocinnamaldehyde motif; a structural element which is present in a number of other important commercial fragrances and odorants. Synthesis Several synthetic routes exist but the most common is a crossed-aldol condensation between piperonal (heliotropin) and propanal followed by selective hydrogenation of the intermediate alkene. This produces a racemic product. See also *Cyclamen aldehyde *Lilial *Hexyl cinnamaldehyde Hexyl cinnamaldehyde (hexyl cinnamal) is a common additive in the perfume and cosmetic industry as aroma substance. It is found naturally in the essential oil of chamomile. It is a pale yellow to yellow liquid to solid, which is nearly insoluble ... References Benzodioxoles Aldehydes Perfume ingredients {{Organic-compound-stub ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
.jpg "Click for more on -> Comet")
propionaldehyd_Formulae_V.1.svg "Click for more on -> Lilial")